近期工作中有使用到 MongoDb作為日誌持久化對象,需要實現對MongoDb的增、刪、改、查,但由於MongoDb的版本比較新,是2.4以上版本的,網上已有的一些MongoDb Helper類都是基於之前MongoDb舊的版本,無法適用於新版本的MongoDb,故我基於MongoDb官方C#驅動重 ...
近期工作中有使用到 MongoDb作為日誌持久化對象,需要實現對MongoDb的增、刪、改、查,但由於MongoDb的版本比較新,是2.4以上版本的,網上已有的一些MongoDb Helper類都是基於之前MongoDb舊的版本,無法適用於新版本的MongoDb,故我基於MongoDb官方C#驅動重新封裝了MongoDbCsharpHelper類(CRUD類),完整代碼如下:
using MongoDB; using MongoDB.Bson; using MongoDB.Driver; using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Linq.Expressions; using System.Reflection; using System.Threading; using System.Web; namespace Zuowj.Utils { /// <summary> /// MongoDbCsharpHelper:MongoDb基於C#語言操作幫助類 /// Author:Zuowenjun /// Date:2017/11/16 /// </summary> public class MongoDbCsharpHelper { private readonly string connectionString = null; private readonly string databaseName = null; private MongoDB.Driver.IMongoDatabase database = null; private readonly bool autoCreateDb = false; private readonly bool autoCreateCollection = false; static MongoDbCsharpHelper() { BsonDefaults.GuidRepresentation = GuidRepresentation.Standard; } public MongoDbCsharpHelper(string mongoConnStr, string dbName, bool autoCreateDb = false, bool autoCreateCollection = false) { this.connectionString = mongoConnStr; this.databaseName = dbName; this.autoCreateDb = autoCreateDb; this.autoCreateCollection = autoCreateCollection; } #region 私有方法 private MongoClient CreateMongoClient() { return new MongoClient(connectionString); } private MongoDB.Driver.IMongoDatabase GetMongoDatabase() { if (database == null) { var client = CreateMongoClient(); if (!DatabaseExists(client, databaseName) && !autoCreateDb) { throw new KeyNotFoundException("此MongoDB名稱不存在:" + databaseName); } database = CreateMongoClient().GetDatabase(databaseName); } return database; } private bool DatabaseExists(MongoClient client, string dbName) { try { var dbNames = client.ListDatabases().ToList().Select(db => db.GetValue("name").AsString); return dbNames.Contains(dbName); } catch //如果連接的賬號不能枚舉出所有DB會報錯,則預設為true { return true; } } private bool CollectionExists(IMongoDatabase database, string collectionName) { var options = new ListCollectionsOptions { Filter = Builders<BsonDocument>.Filter.Eq("name", collectionName) }; return database.ListCollections(options).ToEnumerable().Any(); } private MongoDB.Driver.IMongoCollection<TDoc> GetMongoCollection<TDoc>(string name, MongoCollectionSettings settings = null) { var mongoDatabase = GetMongoDatabase(); if (!CollectionExists(mongoDatabase, name) && !autoCreateCollection) { throw new KeyNotFoundException("此Collection名稱不存在:" + name); } return mongoDatabase.GetCollection<TDoc>(name, settings); } private List<UpdateDefinition<TDoc>> BuildUpdateDefinition<TDoc>(object doc, string parent) { var updateList = new List<UpdateDefinition<TDoc>>(); foreach (var property in typeof(TDoc).GetProperties(BindingFlags.Instance | BindingFlags.Public)) { var key = parent == null ? property.Name : string.Format("{0}.{1}", parent, property.Name); //非空的複雜類型 if ((property.PropertyType.IsClass || property.PropertyType.IsInterface) && property.PropertyType != typeof(string) && property.GetValue(doc) != null) { if (typeof(IList).IsAssignableFrom(property.PropertyType)) { #region 集合類型 int i = 0; var subObj = property.GetValue(doc); foreach (var item in subObj as IList) { if (item.GetType().IsClass || item.GetType().IsInterface) { updateList.AddRange(BuildUpdateDefinition<TDoc>(doc, string.Format("{0}.{1}", key, i))); } else { updateList.Add(Builders<TDoc>.Update.Set(string.Format("{0}.{1}", key, i), item)); } i++; } #endregion } else { #region 實體類型 //複雜類型,導航屬性,類對象和集合對象 var subObj = property.GetValue(doc); foreach (var sub in property.PropertyType.GetProperties(BindingFlags.Instance | BindingFlags.Public)) { updateList.Add(Builders<TDoc>.Update.Set(string.Format("{0}.{1}", key, sub.Name), sub.GetValue(subObj))); } #endregion } } else //簡單類型 { updateList.Add(Builders<TDoc>.Update.Set(key, property.GetValue(doc))); } } return updateList; } private void CreateIndex<TDoc>(IMongoCollection<TDoc> col, string[] indexFields, CreateIndexOptions options = null) { if (indexFields == null) { return; } var indexKeys = Builders<TDoc>.IndexKeys; IndexKeysDefinition<TDoc> keys = null; if (indexFields.Length > 0) { keys = indexKeys.Descending(indexFields[0]); } for (var i = 1; i < indexFields.Length; i++) { var strIndex = indexFields[i]; keys = keys.Descending(strIndex); } if (keys != null) { col.Indexes.CreateOne(keys, options); } } #endregion public void CreateCollectionIndex<TDoc>(string collectionName, string[] indexFields, CreateIndexOptions options = null) { CreateIndex(GetMongoCollection<TDoc>(collectionName), indexFields, options); } public void CreateCollection<TDoc>(string[] indexFields = null, CreateIndexOptions options = null) { string collectionName = typeof(TDoc).Name; CreateCollection<TDoc>(collectionName, indexFields, options); } public void CreateCollection<TDoc>(string collectionName, string[] indexFields = null, CreateIndexOptions options = null) { var mongoDatabase = GetMongoDatabase(); mongoDatabase.CreateCollection(collectionName); CreateIndex(GetMongoCollection<TDoc>(collectionName), indexFields, options); } public List<TDoc> Find<TDoc>(Expression<Func<TDoc, bool>> filter, FindOptions options = null) { string collectionName = typeof(TDoc).Name; return Find<TDoc>(collectionName, filter, options); } public List<TDoc> Find<TDoc>(string collectionName, Expression<Func<TDoc, bool>> filter, FindOptions options = null) { var colleciton = GetMongoCollection<TDoc>(collectionName); return colleciton.Find(filter, options).ToList(); } public List<TDoc> FindByPage<TDoc, TResult>(Expression<Func<TDoc, bool>> filter, Expression<Func<TDoc, TResult>> keySelector, int pageIndex, int pageSize, out int rsCount) { string collectionName = typeof(TDoc).Name; return FindByPage<TDoc, TResult>(collectionName, filter, keySelector, pageIndex, pageSize, out rsCount); } public List<TDoc> FindByPage<TDoc, TResult>(string collectionName, Expression<Func<TDoc, bool>> filter, Expression<Func<TDoc, TResult>> keySelector, int pageIndex, int pageSize, out int rsCount) { var colleciton = GetMongoCollection<TDoc>(collectionName); rsCount = colleciton.AsQueryable().Where(filter).Count(); int pageCount = rsCount / pageSize + ((rsCount % pageSize) > 0 ? 1 : 0); if (pageIndex > pageCount) pageIndex = pageCount; if (pageIndex <= 0) pageIndex = 1; return colleciton.AsQueryable(new AggregateOptions { AllowDiskUse = true }).Where(filter).OrderByDescending(keySelector).Skip((pageIndex - 1) * pageSize).Take(pageSize).ToList(); } public void Insert<TDoc>(TDoc doc, InsertOneOptions options = null) { string collectionName = typeof(TDoc).Name; Insert<TDoc>(collectionName, doc, options); } public void Insert<TDoc>(string collectionName, TDoc doc, InsertOneOptions options = null) { var colleciton = GetMongoCollection<TDoc>(collectionName); colleciton.InsertOne(doc, options); } public void InsertMany<TDoc>(IEnumerable<TDoc> docs, InsertManyOptions options = null) { string collectionName = typeof(TDoc).Name; InsertMany<TDoc>(collectionName, docs, options); } public void InsertMany<TDoc>(string collectionName, IEnumerable<TDoc> docs, InsertManyOptions options = null) { var colleciton = GetMongoCollection<TDoc>(collectionName); colleciton.InsertMany(docs, options); } public void Update<TDoc>(TDoc doc, Expression<Func<TDoc, bool>> filter, UpdateOptions options = null) { string collectionName = typeof(TDoc).Name; var colleciton = GetMongoCollection<TDoc>(collectionName); List<UpdateDefinition<TDoc>> updateList = BuildUpdateDefinition<TDoc>(doc, null); colleciton.UpdateOne(filter, Builders<TDoc>.Update.Combine(updateList), options); } public void Update<TDoc>(string collectionName, TDoc doc, Expression<Func<TDoc, bool>> filter, UpdateOptions options = null) { var colleciton = GetMongoCollection<TDoc>(collectionName); List<UpdateDefinition<TDoc>> updateList = BuildUpdateDefinition<TDoc>(doc, null); colleciton.UpdateOne(filter, Builders<TDoc>.Update.Combine(updateList), options); } public void Update<TDoc>(TDoc doc, Expression<Func<TDoc, bool>> filter, UpdateDefinition<TDoc> updateFields, UpdateOptions options = null) { string collectionName = typeof(TDoc).Name; Update<TDoc>(collectionName, doc, filter, updateFields, options); } public void Update<TDoc>(string collectionName, TDoc doc, Expression<Func<TDoc, bool>> filter, UpdateDefinition<TDoc> updateFields, UpdateOptions options = null) { var colleciton = GetMongoCollection<TDoc>(collectionName); colleciton.UpdateOne(filter, updateFields, options); } public void UpdateMany<TDoc>(TDoc doc, Expression<Func<TDoc, bool>> filter, UpdateOptions options = null) { string collectionName = typeof(TDoc).Name; UpdateMany<TDoc>(collectionName, doc, filter, options); } public void UpdateMany<TDoc>(string collectionName, TDoc doc, Expression<Func<TDoc, bool>> filter, UpdateOptions options = null) { var colleciton = GetMongoCollection<TDoc>(collectionName); List<UpdateDefinition<TDoc>> updateList = BuildUpdateDefinition<TDoc>(doc, null); colleciton.UpdateMany(filter, Builders<TDoc>.Update.Combine(updateList), options); } public void Delete<TDoc>(Expression<Func<TDoc, bool>> filter, DeleteOptions options = null) { string collectionName = typeof(TDoc).Name; Delete<TDoc>(collectionName, filter, options); } public void Delete<TDoc>(string collectionName, Expression<Func<TDoc, bool>> filter, DeleteOptions options = null) { var colleciton = GetMongoCollection<TDoc>(collectionName); colleciton.DeleteOne(filter, options); } public void DeleteMany<TDoc>(Expression<Func<TDoc, bool>> filter, DeleteOptions options = null) { string collectionName = typeof(TDoc).Name; DeleteMany<TDoc>(collectionName, filter, options); } public void DeleteMany<TDoc>(string collectionName, Expression<Func<TDoc, bool>> filter, DeleteOptions options = null) { var colleciton = GetMongoCollection<TDoc>(collectionName); colleciton.DeleteMany(filter, options); } public void ClearCollection<TDoc>(string collectionName) { var colleciton = GetMongoCollection<TDoc>(collectionName); var inddexs = colleciton.Indexes.List(); List<IEnumerable<BsonDocument>> docIndexs = new List<IEnumerable<BsonDocument>>(); while (inddexs.MoveNext()) { docIndexs.Add(inddexs.Current); } var mongoDatabase = GetMongoDatabase(); mongoDatabase.DropCollection(collectionName); if (!CollectionExists(mongoDatabase, collectionName)) { CreateCollection<TDoc>(collectionName); } if (docIndexs.Count > 0) { colleciton = mongoDatabase.GetCollection<TDoc>(collectionName); foreach (var index in docIndexs) { foreach (IndexKeysDefinition<TDoc> indexItem in index) { try { colleciton.Indexes.CreateOne(indexItem); } catch { } } } } } } }
對上述代碼中幾個特別的點進行簡要說明:
1.由於MongoClient.GetDatabase 獲取DB、MongoClient.GetCollection<TDoc> 獲取文檔(也可稱為表)的方法 都有一個特點,即:如果指定的DB名稱、Collection名稱不存在,則會直接創建,但有的時候可能是因為DB名稱、Collection名稱寫錯了導致誤創建了的DB或Collection,那就引起不必要的麻煩,故在MongoDbCsharpHelper類類內部封裝了兩個私有的方法:DatabaseExists(判斷DB是否存在,如是連接的賬號沒有檢索DB的許可權可能會報錯,故代碼中加了直接返回true)、CollectionExists(判斷Collection是否存在);
2.每個CRUD方法,我都分別重載了兩個方法,一個是無需指定Collection名稱,一個是需要指定Collection名稱,為什麼這麼做呢?原因很簡單,因為有時Collection的結構是相同的但又是不同的Collection,這時TDoc是同一個實體類,但collectionName卻是不同的;
3.分頁查詢的時候如果Collection的數據量比較大,那麼就會報類似錯誤:exception: Sort exceeded memory limit of 104857600 bytes, but did not opt in to external sorting. Aborting operation. Pass allowDiskUse:true,根據報錯提示,我們在查詢大數據量時增加AggregateOptions對象,如: colleciton.AsQueryable(new AggregateOptions { AllowDiskUse = true })
4.ClearCollection清除Collection的所有數據,如果Collection的數據量非常大,那麼直接使用colleciton.DeleteMany可能需要很久,有沒有類似SQL SERVER 的truncate table的方法呢?經過多方論證,很遺憾並沒有找到同類功能的方法,只有DropCollection方法,而這個DropCollection方法是直接刪除Collection,當然包括Collection的所有數據,效率也非常高,但是由於是Drop,Collection就不存在了,如果再訪問有可能會報Collection不存在的錯誤,那有沒有好的辦法解決了,當然有,那就是先DropCollection 然後再CreateCollection,最後別忘了把原有的索引插入到新創建的Collection中,這樣就實現了truncate 初始化表的作用,當然在創建索引的時候,有的時候可能報報錯(如:_id),因為_id預設就會被創建索引,再創建可能就會報錯,故colleciton.Indexes.CreateOne外我加了try catch,如果報錯則忽略。
5.CreateCollection(創建集合)、CreateCollectionIndex(創建集合索引)因為有的時候我們需要明確的去創建一個Collection或對已有的Collection創建索引,如果通過shell命令會非常不方便,故在此封裝了一下。
使用示例如下:
var mongoDbHelper = new MongoDbCsharpHelper("MongoDbConnectionString", "LogDB"); mongoDbHelper.CreateCollection<SysLogInfo>("SysLog1",new[]{"LogDT"}); mongoDbHelper.Find<SysLogInfo>("SysLog1", t => t.Level == "Info"); int rsCount=0; mongoDbHelper.FindByPage<SysLogInfo, SysLogInfo>("SysLog1",t=>t.Level=="Info",t=>t,1,20,out rsCount); mongoDbHelper.Insert<SysLogInfo>("SysLog1",new SysLogInfo { LogDT = DateTime.Now, Level = "Info", Msg = "測試消息" }); mongoDbHelper.Update<SysLogInfo>("SysLog1",new SysLogInfo { LogDT = DateTime.Now, Level = "Error", Msg = "測試消息2" },t => t.LogDT==new DateTime(1900,1,1)); mongoDbHelper.Delete<SysLogInfo>(t => t.Level == "Info"); mongoDbHelper.ClearCollection<SysLogInfo>("SysLog1");